In electronic processing of signals, particularly video and other image data signals, it is well known to sharpen an image by providing peaking by using a filter which amplifies high frequency portions of the signal. Sharpening then, results in enhanced edges. This sharpening or peaking technique can however result in signals whose amplitude exceeds the available dynamic range of signal functions which occur subsequently to the point where peaking is applied to the signal. For example, the dynamic range of a film on which an electronically sharpened image is printed, may not accommodate the increased dynamic range of the image produced by the sharpening. In such a situation, any sharpening performed on the image may be lost when the image is printed on such film.
Integral images are images where sharpening may be particularly desirable to enhance visual appearance. Integral image elements which use a lenticular lens sheet, fly's eye lens sheet, or barrier strip sheet and a three-dimensional integral image aligned with the sheet, so that a user can view the three-dimensional image without any special glasses or other equipment, are themselves well known. Such imaging elements and their construction, are described in "Three-Dimensional Imaging Techniques" by Takanori Okoshi, Academic Press, Inc., New York, 1976. Integral image elements having a lenticular lens sheet (that is, a sheet with a plurality of adjacent, parallel, elongated, and partially cylindrical lenses) are also described in the following Unites States patents: U.S. Pat. No. 5,391,254; U.S. Pat. No. 5,424,533; U.S. Pat. No. 5,241,608; U.S. Pat. No. 5,455,689; U.S. Pat. No. 5,276,478; U.S. Pat. No. 5,391,254; U.S. Pat. No. 5,424,533 and others; as well as allowed U.S. patent application Ser. No. 07/931,744.
Integral image elements with a plurality of views to simulate motion of an object in a scene, rather than a three-dimensional image, are also known. It has also been disclosed in U.S. Pat. No. 3,562,941, to move a lenticular image with respect to a lenticular lens sheet so that different images could be viewed from the same location.
Integral image elements with lenticular lens sheets use interlaced vertical image slices which, in the case of a three-dimensional integral image, are aligned with the lenticules so that a three-dimensional image is viewable when the lenticules are vertically oriented with respect to a viewer's eyes. The image may be conveniently laminated (that is, adhered) to an integral or lenticular lens sheet.
Similar integral image elements, such as described in U.S. Pat. No. 3,268,238 and U.S. Pat. No. 3,538,632, can be used to convey a number of individual two-dimensional scenes (such as unrelated scenes or a sequence of scenes depicting motion) rather than one or more three-dimensional images.
Because an integral image uses thin strips or slices from each two-dimensional image, sharpening integral images particularly enhances their perception.
It would be desirable then, to provide a means which allows an image, such as an integral image, to be sharpened particularly using electronic sharpening, and which allows the sharpened image to be reproduced on a suitable media, without losing the enhanced appearance from sharpening.